Dummukha - A Licchavi chieftain. He was present at the discussion of the Nigantha Saccaka with the Buddha, and seeing Saccaka discomfited in the debate, Dummukha compared him to a crab pulled out of a pond and ill treated by village boys (M.i.234).
The Commentary says (MA.i.459) that Dummukha just happened to be his name. He was in reality quite handsome.